Emission control systems, 117 emission control systems – HONDA Motorcycle User Manual
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EMISSION CONTROL SYSTEMS
Source of Emissions
The combustion process produces carbon monoxide and hydrocarbons. Control of hydrocarbons is very important
because under certain conditions, they react to form photochemical smog when subjected to sunlight. Carbon
monoxide does not react in the same way, but it is toxic. Honda Motor Co., Ltd. utilizes lean carburetor settings and
other systems to reduce carbon monoxide and hydrocarbons.
Exhaust Emission Control System
The exhaust emission system consists of a secondary air supply system which introduces filtered air into the
exhaust gases in the exhaust port. No adjustments to this system should be made although periodic inspection of
the components is recommended. The secondary air supply system helps improve emission performance. The
exhaust emission control system is separate from the crankcase emission control system.